1. Field of the Invention
The present invention relates to a light-emitting device and a manufacturing method thereof.
2. Description of the Related Art
Conventionally, a light-emitting device having light-emitting elements has been formed through the following steps of: 1) forming a semiconductor circuit for driving light-emitting elements over a substrate such as a glass substrate by using a semiconductor process, 2) forming an insulating film (planarizing film) over the semiconductor circuit, and 3) forming light-emitting elements over the insulating film. That is, a semiconductor circuit for driving light-emitting elements and light-emitting elements are formed by stacking layers over a substrate in order from the bottom.
Since a light-emitting device manufactured through the conventional manufacturing process has an insulating film over a semiconductor circuit for driving light-emitting elements, and light-emitting elements over the insulating film, there are steps (irregularities) or the like resulting from elements or wires that are formed in the layer below the light-emitting elements (Reference 1: Japanese Patent Laid-Open No. H8-234683). Therefore, the area for forming the light-emitting elements has been limited.
In addition, there may be a case where a coverage defect occurs due to steps resulting from elements or wires that are formed in the layer below the light-emitting elements. Such a coverage defect may cause a point defect, a line defect, or the like.